[Query]set clk rate must operate its coordinated clock
From: Georgi Djakov <hidden>
Date: 2016-06-13 15:59:19
Also in:
linux-clk
On 06/06/2016 11:10 AM, Heiko St?bner wrote:
Hi Mike, Am Freitag, 11. M?rz 2016, 08:51:52 schrieb Michael Turquette:quoted
Quoting Jisheng Zhang (2016-03-08 23:24:20)quoted
I have the following clk case which I dunno the elegant solution: cpuclk have two parents: cpupll and refclk. When set the cpuclk freq, we have to set its parent's freq, I.E cpupll freq. But before changing the cpupll's freq, we should set its refclk as its parent firstly. AFAIK, this is a common case, I have seen such requirement in rockchip, samsung clk driver. They solve this by notifier, but as pointed out by Michael in http://lists.infradead.org/pipermail/linux-arm-kernel/2015-June/351565.ht ml "This is also a hack and it points towards some missing infrastructure in the clock framework." I also don't like the notifier solution, I believe the elegant solution could be using the coordinated clock infrastructure. So what's the status of this infrastructure? I can test, and I can even add some code to make it be ready to be merged if you guide me ;)Thanks for the email. I hope to finish that feature before ELC. I have Cc'd Pi-Cheng Chen from Mediatek who is also interested in coordinated clock rates.pulling this up again, did this materialize yet? :-) Because it looks like on Rockchip we're getting yet another clock that needs special handling (set_rate needs to go through the trusted-firmware, while reading stays the same) which might profit from that as well.
Hi, I am also interested in the CCR. Hopefully Mike will post some patches on the list soon. Regards, Georgi